This page explains how Ray Zhang (USATT# 214874)'s rating went from 1620 to 1570 at the 2021 Joola North American Team held on 26 Nov 2021 - 28 Nov 2021. The links below take you to pages that describe various aspects of the rating processor.

The rating processor goes through 4 passes in order. The links take you to pages that provide detailed explanations of the calculations during each of the 4 passes.